<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * Unit tests for user/lib.php.
 *
 * @package    core_user
 * @category   phpunit
 * @copyright  2013 Rajesh Taneja <rajesh@moodle.com>
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

defined('MOODLE_INTERNAL') || die();

global $CFG;
require_once($CFG->dirroot.'/user/lib.php');

/**
 * Unit tests for user lib api.
 *
 * @package    core_user
 * @category   phpunit
 * @copyright  2013 Rajesh Taneja <rajesh@moodle.com>
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
class core_userliblib_testcase extends advanced_testcase {
    /**
     * Test user_get_user_details_courses
     */
    public function test_user_get_user_details_courses() {
        global $DB;

        $this->resetAfterTest();

        // Create user and modify user profile.
        $user1 = $this->getDataGenerator()->create_user();
        $user2 = $this->getDataGenerator()->create_user();
        $user3 = $this->getDataGenerator()->create_user();

        $course1 = $this->getDataGenerator()->create_course();
        $coursecontext = context_course::instance($course1->id);
        $teacherrole = $DB->get_record('role', array('shortname' => 'teacher'));
        $this->getDataGenerator()->enrol_user($user1->id, $course1->id);
        $this->getDataGenerator()->enrol_user($user2->id, $course1->id);
        role_assign($teacherrole->id, $user1->id, $coursecontext->id);
        role_assign($teacherrole->id, $user2->id, $coursecontext->id);

        accesslib_clear_all_caches_for_unit_testing();

        // Get user2 details as a user with super system capabilities.
        $result = user_get_user_details_courses($user2);
        $this->assertEquals($user2->id, $result['id']);
        $this->assertEquals(fullname($user2), $result['fullname']);
        $this->assertEquals($course1->id, $result['enrolledcourses'][0]['id']);

        $this->setUser($user1);
        // Get user2 details as a user who can only see this user in a course.
        $result = user_get_user_details_courses($user2);
        $this->assertEquals($user2->id, $result['id']);
        $this->assertEquals(fullname($user2), $result['fullname']);
        $this->assertEquals($course1->id, $result['enrolledcourses'][0]['id']);

        // Get user2 details as a user who doesn't share any course with user2.
        $this->setUser($user3);
        $result = user_get_user_details_courses($user2);
        $this->assertNull($result);
    }

    /**
     * Verify return when course groupmode set to 'no groups'.
     */
    public function test_user_get_user_details_courses_groupmode_nogroups() {
        $this->resetAfterTest();

        // Enrol 2 users into a course with groupmode set to 'no groups'.
        // Profiles should be visible.
        $user1 = $this->getDataGenerator()->create_user();
        $user2 = $this->getDataGenerator()->create_user();
        $course = $this->getDataGenerator()->create_course((object) ['groupmode' => 0]);
        $this->getDataGenerator()->enrol_user($user1->id, $course->id);
        $this->getDataGenerator()->enrol_user($user2->id, $course->id);

        $this->setUser($user1);
        $userdetails = user_get_user_details_courses($user2);
        $this->assertInternalType('array', $userdetails);
        $this->assertEquals($user2->id, $userdetails['id']);
    }

    /**
     * Verify return when course groupmode set to 'separate groups'.
     */
    public function test_user_get_user_details_courses_groupmode_separate() {
        $this->resetAfterTest();

        // Enrol 2 users into a course with groupmode set to 'separate groups'.
        // The users are not in any groups, so profiles should be hidden (same as if they were in separate groups).
        $user1 = $this->getDataGenerator()->create_user();
        $user2 = $this->getDataGenerator()->create_user();
        $course = $this->getDataGenerator()->create_course((object) ['groupmode' => 1]);
        $this->getDataGenerator()->enrol_user($user1->id, $course->id);
        $this->getDataGenerator()->enrol_user($user2->id, $course->id);

        $this->setUser($user1);
        $this->assertNull(user_get_user_details_courses($user2));
    }

    /**
     * Verify return when course groupmode set to 'visible groups'.
     */
    public function test_user_get_user_details_courses_groupmode_visible() {
        $this->resetAfterTest();

        // Enrol 2 users into a course with groupmode set to 'visible groups'.
        // The users are not in any groups, and profiles should be visible because of the groupmode.
        $user1 = $this->getDataGenerator()->create_user();
        $user2 = $this->getDataGenerator()->create_user();
        $course = $this->getDataGenerator()->create_course((object) ['groupmode' => 2]);
        $this->getDataGenerator()->enrol_user($user1->id, $course->id);
        $this->getDataGenerator()->enrol_user($user2->id, $course->id);

        $this->setUser($user1);
        $userdetails = user_get_user_details_courses($user2);
        $this->assertInternalType('array', $userdetails);
        $this->assertEquals($user2->id, $userdetails['id']);
    }

    /**
     * Test user_update_user.
     */
    public function test_user_update_user() {
        global $DB;

        $this->resetAfterTest();

        // Create user and modify user profile.
        $user = $this->getDataGenerator()->create_user();
        $user->firstname = 'Test';
        $user->password = 'M00dLe@T';

        // Update user and capture event.
        $sink = $this->redirectEvents();
        user_update_user($user);
        $events = $sink->get_events();
        $sink->close();
        $event = array_pop($events);

        // Test updated value.
        $dbuser = $DB->get_record('user', array('id' => $user->id));
        $this->assertSame($user->firstname, $dbuser->firstname);
        $this->assertNotSame('M00dLe@T', $dbuser->password);

        // Test event.
        $this->assertInstanceOf('\core\event\user_updated', $event);
        $this->assertSame($user->id, $event->objectid);
        $this->assertSame('user_updated', $event->get_legacy_eventname());
        $this->assertEventLegacyData($dbuser, $event);
        $this->assertEquals(context_user::instance($user->id), $event->get_context());
        $expectedlogdata = array(SITEID, 'user', 'update', 'view.php?id='.$user->id, '');
        $this->assertEventLegacyLogData($expectedlogdata, $event);

        // Update user with no password update.
        $password = $user->password = hash_internal_user_password('M00dLe@T');
        user_update_user($user, false);
        $dbuser = $DB->get_record('user', array('id' => $user->id));
        $this->assertSame($password, $dbuser->password);

        // Verify event is not triggred by user_update_user when needed.
        $sink = $this->redirectEvents();
        user_update_user($user, false, false);
        $events = $sink->get_events();
        $sink->close();
        $this->assertCount(0, $events);

        // With password, there should be 1 event.
        $sink = $this->redirectEvents();
        user_update_user($user, true, false);
        $events = $sink->get_events();
        $sink->close();
        $this->assertCount(1, $events);
        $event = array_pop($events);
        $this->assertInstanceOf('\core\event\user_password_updated', $event);

        // Test user data validation.
        $user->username = 'johndoe123';
        $user->auth = 'shibolth';
        $user->country = 'WW';
        $user->lang = 'xy';
        $user->theme = 'somewrongthemename';
        $user->timezone = '30.5';
        $user->url = 'wwww.somewrong@#$url.com.aus';
        $debugmessages = $this->getDebuggingMessages();
        user_update_user($user, true, false);
        $this->assertDebuggingCalledCount(6, $debugmessages);

        // Now, with valid user data.
        $user->username = 'johndoe321';
        $user->auth = 'shibboleth';
        $user->country = 'AU';
        $user->lang = 'en';
        $user->theme = 'classic';
        $user->timezone = 'Australia/Perth';
        $user->url = 'www.moodle.org';
        user_update_user($user, true, false);
        $this->assertDebuggingNotCalled();
    }

    /**
     * Test create_users.
     */
    public function test_create_users() {
        global $DB;

        $this->resetAfterTest();

        $user = array(
            'username' => 'usernametest1',
            'password' => 'Moodle2012!',
            'idnumber' => 'idnumbertest1',
            'firstname' => 'First Name User Test 1',
            'lastname' => 'Last Name User Test 1',
            'middlename' => 'Middle Name User Test 1',
            'lastnamephonetic' => '最後のお名前のテスト一号',
            'firstnamephonetic' => 'お名前のテスト一号',
            'alternatename' => 'Alternate Name User Test 1',
            'email' => 'usertest1@example.com',
            'description' => 'This is a description for user 1',
            'city' => 'Perth',
            'country' => 'AU'
            );

        // Create user and capture event.
        $sink = $this->redirectEvents();
        $user['id'] = user_create_user($user);
        $events = $sink->get_events();
        $sink->close();
        $event = array_pop($events);

        // Test user info in DB.
        $dbuser = $DB->get_record('user', array('id' => $user['id']));
        $this->assertEquals($dbuser->username, $user['username']);
        $this->assertEquals($dbuser->idnumber, $user['idnumber']);
        $this->assertEquals($dbuser->firstname, $user['firstname']);
        $this->assertEquals($dbuser->lastname, $user['lastname']);
        $this->assertEquals($dbuser->email, $user['email']);
        $this->assertEquals($dbuser->description, $user['description']);
        $this->assertEquals($dbuser->city, $user['city']);
        $this->assertEquals($dbuser->country, $user['country']);

        // Test event.
        $this->assertInstanceOf('\core\event\user_created', $event);
        $this->assertEquals($user['id'], $event->objectid);
        $this->assertEquals('user_created', $event->get_legacy_eventname());
        $this->assertEquals(context_user::instance($user['id']), $event->get_context());
        $this->assertEventLegacyData($dbuser, $event);
        $expectedlogdata = array(SITEID, 'user', 'add', '/view.php?id='.$event->objectid, fullname($dbuser));
        $this->assertEventLegacyLogData($expectedlogdata, $event);

        // Verify event is not triggred by user_create_user when needed.
        $user = array('username' => 'usernametest2'); // Create another user.
        $sink = $this->redirectEvents();
        user_create_user($user, true, false);
        $events = $sink->get_events();
        $sink->close();
        $this->assertCount(0, $events);

        // Test user data validation, first some invalid data.
        $user['username'] = 'johndoe123';
        $user['auth'] = 'shibolth';
        $user['country'] = 'WW';
        $user['lang'] = 'xy';
        $user['theme'] = 'somewrongthemename';
        $user['timezone'] = '-30.5';
        $user['url'] = 'wwww.somewrong@#$url.com.aus';
        $debugmessages = $this->getDebuggingMessages();
        $user['id'] = user_create_user($user, true, false);
        $this->assertDebuggingCalledCount(6, $debugmessages);
        $dbuser = $DB->get_record('user', array('id' => $user['id']));
        $this->assertEquals($dbuser->country, 0);
        $this->assertEquals($dbuser->lang, 'en');
        $this->assertEquals($dbuser->timezone, '');

        // Now, with valid user data.
        $user['username'] = 'johndoe321';
        $user['auth'] = 'shibboleth';
        $user['country'] = 'AU';
        $user['lang'] = 'en';
        $user['theme'] = 'classic';
        $user['timezone'] = 'Australia/Perth';
        $user['url'] = 'www.moodle.org';
        user_create_user($user, true, false);
        $this->assertDebuggingNotCalled();
    }

    /**
     * Test that {@link user_create_user()} throws exception when invalid username is provided.
     *
     * @dataProvider data_create_user_invalid_username
     * @param string $username Invalid username
     * @param string $expectmessage Expected exception message
     */
    public function test_create_user_invalid_username($username, $expectmessage) {
        global $CFG;

        $this->resetAfterTest();
        $CFG->extendedusernamechars = false;

        $user = [
            'username' => $username,
        ];

        $this->expectException('moodle_exception');
        $this->expectExceptionMessage($expectmessage);

        user_create_user($user);
    }

    /**
     * Data provider for {@link self::test_create_user_invalid_username()}.
     *
     * @return array
     */
    public function data_create_user_invalid_username() {
        return [
            'empty_string' => [
                '',
                'The username cannot be blank',
            ],
            'only_whitespace' => [
                "\t\t  \t\n ",
                'The username cannot be blank',
            ],
            'lower_case' => [
                'Mudrd8mz',
                'The username must be in lower case',
            ],
            'extended_chars' => [
                'dmudrák',
                'The given username contains invalid characters',
            ],
        ];
    }

    /**
     * Test function user_count_login_failures().
     */
    public function test_user_count_login_failures() {
        $this->resetAfterTest();
        $user = $this->getDataGenerator()->create_user();
        $this->assertEquals(0, get_user_preferences('login_failed_count_since_success', 0, $user));
        for ($i = 0; $i < 10; $i++) {
            login_attempt_failed($user);
        }
        $this->assertEquals(10, get_user_preferences('login_failed_count_since_success', 0, $user));
        $count = user_count_login_failures($user); // Reset count.
        $this->assertEquals(10, $count);
        $this->assertEquals(0, get_user_preferences('login_failed_count_since_success', 0, $user));

        for ($i = 0; $i < 10; $i++) {
            login_attempt_failed($user);
        }
        $this->assertEquals(10, get_user_preferences('login_failed_count_since_success', 0, $user));
        $count = user_count_login_failures($user, false); // Do not reset count.
        $this->assertEquals(10, $count);
        $this->assertEquals(10, get_user_preferences('login_failed_count_since_success', 0, $user));
    }

    /**
     * Test function user_add_password_history().
     */
    public function test_user_add_password_history() {
        global $DB;

        $this->resetAfterTest();

        $user1 = $this->getDataGenerator()->create_user();
        $user2 = $this->getDataGenerator()->create_user();
        $user3 = $this->getDataGenerator()->create_user();
        $DB->delete_records('user_password_history', array());

        set_config('passwordreuselimit', 0);

        user_add_password_history($user1->id, 'pokus');
        $this->assertEquals(0, $DB->count_records('user_password_history'));

        // Test adding and discarding of old.

        set_config('passwordreuselimit', 3);

        user_add_password_history($user1->id, 'pokus');
        $this->assertEquals(1, $DB->count_records('user_password_history'));
        $this->assertEquals(1, $DB->count_records('user_password_history', array('userid' => $user1->id)));

        user_add_password_history($user1->id, 'pokus2');
        user_add_password_history($user1->id, 'pokus3');
        user_add_password_history($user1->id, 'pokus4');
        $this->assertEquals(3, $DB->count_records('user_password_history'));
        $this->assertEquals(3, $DB->count_records('user_password_history', array('userid' => $user1->id)));

        user_add_password_history($user2->id, 'pokus1');
        $this->assertEquals(4, $DB->count_records('user_password_history'));
        $this->assertEquals(3, $DB->count_records('user_password_history', array('userid' => $user1->id)));
        $this->assertEquals(1, $DB->count_records('user_password_history', array('userid' => $user2->id)));

        user_add_password_history($user2->id, 'pokus2');
        user_add_password_history($user2->id, 'pokus3');
        $this->assertEquals(3, $DB->count_records('user_password_history', array('userid' => $user2->id)));

        $ids = array_keys($DB->get_records('user_password_history', array('userid' => $user2->id), 'timecreated ASC, id ASC'));
        user_add_password_history($user2->id, 'pokus4');
        $this->assertEquals(3, $DB->count_records('user_password_history', array('userid' => $user2->id)));
        $newids = array_keys($DB->get_records('user_password_history', array('userid' => $user2->id), 'timecreated ASC, id ASC'));

        $removed = array_shift($ids);
        $added = array_pop($newids);
        $this->assertSame($ids, $newids);
        $this->assertGreaterThan($removed, $added);

        // Test disabling prevents changes.

        set_config('passwordreuselimit', 0);

        $this->assertEquals(6, $DB->count_records('user_password_history'));

        $ids = array_keys($DB->get_records('user_password_history', array('userid' => $user2->id), 'timecreated ASC, id ASC'));
        user_add_password_history($user2->id, 'pokus5');
        user_add_password_history($user3->id, 'pokus1');
        $newids = array_keys($DB->get_records('user_password_history', array('userid' => $user2->id), 'timecreated ASC, id ASC'));
        $this->assertSame($ids, $newids);
        $this->assertEquals(6, $DB->count_records('user_password_history'));

        set_config('passwordreuselimit', -1);

        $ids = array_keys($DB->get_records('user_password_history', array('userid' => $user2->id), 'timecreated ASC, id ASC'));
        user_add_password_history($user2->id, 'pokus6');
        user_add_password_history($user3->id, 'pokus6');
        $newids = array_keys($DB->get_records('user_password_history', array('userid' => $user2->id), 'timecreated ASC, id ASC'));
        $this->assertSame($ids, $newids);
        $this->assertEquals(6, $DB->count_records('user_password_history'));
    }

    /**
     * Test function user_add_password_history().
     */
    public function test_user_is_previously_used_password() {
        global $DB;

        $this->resetAfterTest();

        $user1 = $this->getDataGenerator()->create_user();
        $user2 = $this->getDataGenerator()->create_user();
        $DB->delete_records('user_password_history', array());

        set_config('passwordreuselimit', 0);

        user_add_password_history($user1->id, 'pokus');
        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus'));

        set_config('passwordreuselimit', 3);

        user_add_password_history($user2->id, 'pokus1');
        user_add_password_history($user2->id, 'pokus2');

        user_add_password_history($user1->id, 'pokus1');
        $this->assertTrue(user_is_previously_used_password($user1->id, 'pokus1'));
        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus2'));
        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus3'));
        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus4'));

        user_add_password_history($user1->id, 'pokus2');
        $this->assertTrue(user_is_previously_used_password($user1->id, 'pokus1'));
        $this->assertTrue(user_is_previously_used_password($user1->id, 'pokus2'));
        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus3'));
        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus4'));

        user_add_password_history($user1->id, 'pokus3');
        $this->assertTrue(user_is_previously_used_password($user1->id, 'pokus1'));
        $this->assertTrue(user_is_previously_used_password($user1->id, 'pokus2'));
        $this->assertTrue(user_is_previously_used_password($user1->id, 'pokus3'));
        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus4'));

        user_add_password_history($user1->id, 'pokus4');
        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus1'));
        $this->assertTrue(user_is_previously_used_password($user1->id, 'pokus2'));
        $this->assertTrue(user_is_previously_used_password($user1->id, 'pokus3'));
        $this->assertTrue(user_is_previously_used_password($user1->id, 'pokus4'));

        set_config('passwordreuselimit', 2);

        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus1'));
        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus2'));
        $this->assertTrue(user_is_previously_used_password($user1->id, 'pokus3'));
        $this->assertTrue(user_is_previously_used_password($user1->id, 'pokus4'));

        set_config('passwordreuselimit', 3);

        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus1'));
        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus2'));
        $this->assertTrue(user_is_previously_used_password($user1->id, 'pokus3'));
        $this->assertTrue(user_is_previously_used_password($user1->id, 'pokus4'));

        set_config('passwordreuselimit', 0);

        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus1'));
        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus2'));
        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus3'));
        $this->assertFalse(user_is_previously_used_password($user1->id, 'pokus4'));
    }

    /**
     * Test that password history is deleted together with user.
     */
    public function test_delete_of_hashes_on_user_delete() {
        global $DB;

        $this->resetAfterTest();

        $user1 = $this->getDataGenerator()->create_user();
        $user2 = $this->getDataGenerator()->create_user();
        $DB->delete_records('user_password_history', array());

        set_config('passwordreuselimit', 3);

        user_add_password_history($user1->id, 'pokus');
        user_add_password_history($user2->id, 'pokus1');
        user_add_password_history($user2->id, 'pokus2');

        $this->assertEquals(3, $DB->count_records('user_password_history'));
        $this->assertEquals(1, $DB->count_records('user_password_history', array('userid' => $user1->id)));
        $this->assertEquals(2, $DB->count_records('user_password_history', array('userid' => $user2->id)));

        delete_user($user2);
        $this->assertEquals(1, $DB->count_records('user_password_history'));
        $this->assertEquals(1, $DB->count_records('user_password_history', array('userid' => $user1->id)));
        $this->assertEquals(0, $DB->count_records('user_password_history', array('userid' => $user2->id)));
    }

    /**
     * Test user_list_view function
     */
    public function test_user_list_view() {

        $this->resetAfterTest();

        // Course without sections.
        $course = $this->getDataGenerator()->create_course();
        $context = context_course::instance($course->id);

        $this->setAdminUser();

        // Redirect events to the sink, so we can recover them later.
        $sink = $this->redirectEvents();

        user_list_view($course, $context);
        $events = $sink->get_events();
        $this->assertCount(1, $events);
        $event = reset($events);

        // Check the event details are correct.
        $this->assertInstanceOf('\core\event\user_list_viewed', $event);
        $this->assertEquals($context, $event->get_context());
        $this->assertEquals($course->shortname, $event->other['courseshortname']);
        $this->assertEquals($course->fullname, $event->other['coursefullname']);

    }

    /**
     * Test setting the user menu avatar size.
     */
    public function test_user_menu_custom_avatar_size() {
        global $PAGE;
        $this->resetAfterTest(true);

        $testsize = 100;

        $PAGE->set_url('/');
        $user = $this->getDataGenerator()->create_user();
        $opts = user_get_user_navigation_info($user, $PAGE, array('avatarsize' => $testsize));
        $avatarhtml = $opts->metadata['useravatar'];

        $matches = [];
        preg_match('/(?:.*width=")(\d*)(?:" height=")(\d*)(?:".*\/>)/', $avatarhtml, $matches);
        $this->assertCount(3, $matches);

        $this->assertEquals(intval($matches[1]), $testsize);
        $this->assertEquals(intval($matches[2]), $testsize);
    }

    /**
     * Test user_can_view_profile
     */
    public function test_user_can_view_profile() {
        global $DB, $CFG;

        $this->resetAfterTest();

        // Create five users.
        $user1 = $this->getDataGenerator()->create_user();
        $user2 = $this->getDataGenerator()->create_user();
        $user3 = $this->getDataGenerator()->create_user();
        $user4 = $this->getDataGenerator()->create_user();
        $user5 = $this->getDataGenerator()->create_user();
        $user6 = $this->getDataGenerator()->create_user(array('deleted' => 1));
        $user7 = $this->getDataGenerator()->create_user();
        $user8 = $this->getDataGenerator()->create_user();
        $user8->id = 0; // Visitor.

        $studentrole = $DB->get_record('role', array('shortname' => 'student'));
        // Add the course creator role to the course contact and assign a user to that role.
        $CFG->coursecontact = '2';
        $coursecreatorrole = $DB->get_record('role', array('shortname' => 'coursecreator'));
        $this->getDataGenerator()->role_assign($coursecreatorrole->id, $user7->id);

         // Create two courses.
        $course1 = $this->getDataGenerator()->create_course();
        $course2 = $this->getDataGenerator()->create_course();
        $coursecontext = context_course::instance($course2->id);
        // Prepare another course with separate groups and groupmodeforce set to true.
        $record = new stdClass();
        $record->groupmode = 1;
        $record->groupmodeforce = 1;
        $course3 = $this->getDataGenerator()->create_course($record);
        // Enrol users 1 and 2 in first course.
        $this->getDataGenerator()->enrol_user($user1->id, $course1->id);
        $this->getDataGenerator()->enrol_user($user2->id, $course1->id);
        // Enrol users 2 and 3 in second course.
        $this->getDataGenerator()->enrol_user($user2->id, $course2->id);
        $this->getDataGenerator()->enrol_user($user3->id, $course2->id);
        // Enrol users 1, 4, and 5 into course 3.
        $this->getDataGenerator()->enrol_user($user1->id, $course3->id);
        $this->getDataGenerator()->enrol_user($user4->id, $course3->id);
        $this->getDataGenerator()->enrol_user($user5->id, $course3->id);

        // User 3 should not be able to see user 1, either by passing their own course (course 2) or user 1's course (course 1).
        $this->setUser($user3);
        $this->assertFalse(user_can_view_profile($user1, $course2));
        $this->assertFalse(user_can_view_profile($user1, $course1));

        // Remove capability moodle/user:viewdetails in course 2.
        assign_capability('moodle/user:viewdetails', CAP_PROHIBIT, $studentrole->id, $coursecontext);
        // Set current user to user 1.
        $this->setUser($user1);
        // User 1 can see User 1's profile.
        $this->assertTrue(user_can_view_profile($user1));

        $tempcfg = $CFG->forceloginforprofiles;
        $CFG->forceloginforprofiles = 0;
        // Not forced to log in to view profiles, should be able to see all profiles besides user 6.
        $users = array($user1, $user2, $user3, $user4, $user5, $user7);
        foreach ($users as $user) {
            $this->assertTrue(user_can_view_profile($user));
        }
        // Restore setting.
        $CFG->forceloginforprofiles = $tempcfg;

        // User 1 can not see user 6 as they have been deleted.
        $this->assertFalse(user_can_view_profile($user6));
        // User 1 can see User 7 as they are a course contact.
        $this->assertTrue(user_can_view_profile($user7));
        // User 1 is in a course with user 2 and has the right capability - return true.
        $this->assertTrue(user_can_view_profile($user2));
        // User 1 is not in a course with user 3 - return false.
        $this->assertFalse(user_can_view_profile($user3));

        // Set current user to user 2.
        $this->setUser($user2);
        // User 2 is in a course with user 3 but does not have the right capability - return false.
        $this->assertFalse(user_can_view_profile($user3));

        // Set user 1 in one group and users 4 and 5 in another group.
        $group1 = $this->getDataGenerator()->create_group(array('courseid' => $course3->id));
        $group2 = $this->getDataGenerator()->create_group(array('courseid' => $course3->id));
        groups_add_member($group1->id, $user1->id);
        groups_add_member($group2->id, $user4->id);
        groups_add_member($group2->id, $user5->id);
        $this->setUser($user1);
        // Check that user 1 can not see user 4.
        $this->assertFalse(user_can_view_profile($user4));
        // Check that user 5 can see user 4.
        $this->setUser($user5);
        $this->assertTrue(user_can_view_profile($user4));

        // Test the user:viewalldetails cap check using the course creator role which, by default, can't see student profiles.
        $this->setUser($user7);
        $this->assertFalse(user_can_view_profile($user4));
        assign_capability('moodle/user:viewalldetails', CAP_ALLOW, $coursecreatorrole->id, context_system::instance()->id, true);
        reload_all_capabilities();
        $this->assertTrue(user_can_view_profile($user4));
        unassign_capability('moodle/user:viewalldetails', $coursecreatorrole->id, $coursecontext->id);
        reload_all_capabilities();

        $CFG->coursecontact = null;

        // Visitor (Not a guest user, userid=0).
        $CFG->forceloginforprofiles = 1;
        $this->setUser($user8);
        $this->assertFalse(user_can_view_profile($user1));

        // Let us test with guest user.
        $this->setGuestUser();
        $CFG->forceloginforprofiles = 1;
        foreach ($users as $user) {
            $this->assertFalse(user_can_view_profile($user));
        }

        // Even with cap, still guests should not be allowed in.
        $guestrole = $DB->get_records_menu('role', array('shortname' => 'guest'), 'id', 'archetype, id');
        assign_capability('moodle/user:viewdetails', CAP_ALLOW, $guestrole['guest'], context_system::instance()->id, true);
        reload_all_capabilities();
        foreach ($users as $user) {
            $this->assertFalse(user_can_view_profile($user));
        }

        $CFG->forceloginforprofiles = 0;
        foreach ($users as $user) {
            $this->assertTrue(user_can_view_profile($user));
        }

        // Let us test with Visitor user.
        $this->setUser($user8);
        $CFG->forceloginforprofiles = 1;
        foreach ($users as $user) {
            $this->assertFalse(user_can_view_profile($user));
        }

        $CFG->forceloginforprofiles = 0;
        foreach ($users as $user) {
            $this->assertTrue(user_can_view_profile($user));
        }

        // Testing non-shared courses where capabilities are met, using system role overrides.
        $CFG->forceloginforprofiles = $tempcfg;
        $course4 = $this->getDataGenerator()->create_course();
        $this->getDataGenerator()->enrol_user($user1->id, $course4->id);

        // Assign a manager role at the system context.
        $managerrole = $DB->get_record('role', array('shortname' => 'manager'));
        $user9 = $this->getDataGenerator()->create_user();
        $this->getDataGenerator()->role_assign($managerrole->id, $user9->id);

        // Make sure viewalldetails and viewdetails are overridden to 'prevent' (i.e. can be overridden at a lower context).
        $systemcontext = context_system::instance();
        assign_capability('moodle/user:viewdetails', CAP_PREVENT, $managerrole->id, $systemcontext, true);
        assign_capability('moodle/user:viewalldetails', CAP_PREVENT, $managerrole->id, $systemcontext, true);

        // And override these to 'Allow' in a specific course.
        $course4context = context_course::instance($course4->id);
        assign_capability('moodle/user:viewalldetails', CAP_ALLOW, $managerrole->id, $course4context, true);
        assign_capability('moodle/user:viewdetails', CAP_ALLOW, $managerrole->id, $course4context, true);

        // The manager now shouldn't have viewdetails in the system or user context.
        $this->setUser($user9);
        $user1context = context_user::instance($user1->id);
        $this->assertFalse(has_capability('moodle/user:viewdetails', $systemcontext));
        $this->assertFalse(has_capability('moodle/user:viewdetails', $user1context));

        // Confirm that user_can_view_profile() returns true for $user1 when called without $course param. It should find $course1.
        $this->assertTrue(user_can_view_profile($user1));

        // Confirm this also works when restricting scope to just that course.
        $this->assertTrue(user_can_view_profile($user1, $course4));
    }

    /**
     * Test user_get_user_details
     */
    public function test_user_get_user_details() {
        global $DB;

        $this->resetAfterTest();

        // Create user and modify user profile.
        $teacher = $this->getDataGenerator()->create_user();
        $student = $this->getDataGenerator()->create_user();
        $studentfullname = fullname($student);

        $course1 = $this->getDataGenerator()->create_course();
        $coursecontext = context_course::instance($course1->id);
        $teacherrole = $DB->get_record('role', array('shortname' => 'teacher'));
        $studentrole = $DB->get_record('role', array('shortname' => 'student'));
        $this->getDataGenerator()->enrol_user($teacher->id, $course1->id);
        $this->getDataGenerator()->enrol_user($student->id, $course1->id);
        role_assign($teacherrole->id, $teacher->id, $coursecontext->id);
        role_assign($studentrole->id, $student->id, $coursecontext->id);

        accesslib_clear_all_caches_for_unit_testing();

        // Get student details as a user with super system capabilities.
        $result = user_get_user_details($student, $course1);
        $this->assertEquals($student->id, $result['id']);
        $this->assertEquals($studentfullname, $result['fullname']);
        $this->assertEquals($course1->id, $result['enrolledcourses'][0]['id']);

        $this->setUser($teacher);
        // Get student details as a user who can only see this user in a course.
        $result = user_get_user_details($student, $course1);
        $this->assertEquals($student->id, $result['id']);
        $this->assertEquals($studentfullname, $result['fullname']);
        $this->assertEquals($course1->id, $result['enrolledcourses'][0]['id']);

        // Get student details with required fields.
        $result = user_get_user_details($student, $course1, array('id', 'fullname'));
        $this->assertCount(2, $result);
        $this->assertEquals($student->id, $result['id']);
        $this->assertEquals($studentfullname, $result['fullname']);

        // Get exception for invalid required fields.
        $this->expectException('moodle_exception');
        $result = user_get_user_details($student, $course1, array('wrongrequiredfield'));
    }

    /**
     * Regression test for MDL-57840.
     *
     * Ensure the fields "auth, confirmed, idnumber, lang, theme, timezone and mailformat" are present when
     * calling user_get_user_details() function.
     */
    public function test_user_get_user_details_missing_fields() {
        global $CFG;

        $this->resetAfterTest(true);
        $this->setAdminUser(); // We need capabilities to view the data.
        $user = self::getDataGenerator()->create_user([
                                                          'auth'       => 'auth_something',
                                                          'confirmed'  => '0',
                                                          'idnumber'   => 'someidnumber',
                                                          'lang'       => 'en',
                                                          'theme'      => $CFG->theme,
                                                          'timezone'   => '50',
                                                          'mailformat' => '0',
                                                      ]);

        // Fields that should get by default.
        $got = user_get_user_details($user);
        self::assertSame('auth_something', $got['auth']);
        self::assertSame('0', $got['confirmed']);
        self::assertSame('someidnumber', $got['idnumber']);
        self::assertSame('en', $got['lang']);
        self::assertSame($CFG->theme, $got['theme']);
        self::assertSame('50', $got['timezone']);
        self::assertSame('0', $got['mailformat']);
    }

    /**
     * Test returning the total number of participants.
     */
    public function test_user_get_total_participants() {
        global $DB;

        $this->resetAfterTest();

        // Create a course.
        $course = self::getDataGenerator()->create_course();

        // Create a teacher.
        $teacher = self::getDataGenerator()->create_user(['firstname' => 'searchforthis']);

        // Create a bunch of students.
        $student1 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis']);
        $student2 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis']);
        $student3 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis']);

        // Create a group.
        $group = self::getDataGenerator()->create_group(array('courseid' => $course->id));

        // Enrol the students.
        self::getDataGenerator()->enrol_user($student1->id, $course->id);
        self::getDataGenerator()->enrol_user($student2->id, $course->id);
        self::getDataGenerator()->enrol_user($student3->id, $course->id);

        // Enrol the teacher.
        $roleids = $DB->get_records_menu('role', null, '', 'shortname, id');
        self::getDataGenerator()->enrol_user($teacher->id, $course->id, $roleids['editingteacher']);

        // Add the teacher and two of the students to the group.
        groups_add_member($group->id, $teacher->id);
        groups_add_member($group->id, $student1->id);
        groups_add_member($group->id, $student2->id);

        // Set it so the teacher and two of the students have accessed the courses within the last day,
        // but only one of the students is in the group.
        $accesssince = time() - DAYSECS;
        $lastaccess = new stdClass();
        $lastaccess->userid = $teacher->id;
        $lastaccess->courseid = $course->id;
        $lastaccess->timeaccess = time() - DAYSECS;
        $DB->insert_record('user_lastaccess', $lastaccess);

        $lastaccess->userid = $student1->id;
        $DB->insert_record('user_lastaccess', $lastaccess);

        $lastaccess->userid = $student3->id;
        $DB->insert_record('user_lastaccess', $lastaccess);

        // Now, when we perform the following search we should only return 1 user. A student who belongs to
        // the group and has the name 'searchforthis' and has also accessed the course in the last day.
        $count = user_get_total_participants($course->id, $group->id, $accesssince + 1, $roleids['student'], 0, -1,
            'searchforthis');

        $this->assertEquals(1, $count);
    }

    /**
     * Test returning the number of participants on the front page.
     */
    public function test_user_get_total_participants_on_front_page() {
        $this->resetAfterTest();

        // Set it so that only 3 users have accessed the site within the last day.
        $accesssince = time() - DAYSECS;

        // Create a bunch of users.
        $user1 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis', 'lastaccess' => $accesssince]);
        $user2 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis', 'lastaccess' => $accesssince]);
        $user3 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis']);
        $user4 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis', 'lastaccess' => $accesssince]);

        // Create a group.
        $group = self::getDataGenerator()->create_group(array('courseid' => SITEID));

        // Add 3 of the users to a group.
        groups_add_member($group->id, $user1->id);
        groups_add_member($group->id, $user2->id);
        groups_add_member($group->id, $user3->id);

        // Now, when we perform the following search we should only return 2 users. Users who belong to
        // the group and have the name 'searchforthis' and have also accessed the site in the last day.
        $count = user_get_total_participants(SITEID, $group->id, $accesssince + 1, 0, 0, -1, 'searchforthis');

        $this->assertEquals(2, $count);
    }

    /**
     * Test returning the participants.
     */
    public function test_user_get_participants() {
        global $DB;

        $this->resetAfterTest();

        // Create a course.
        $course = self::getDataGenerator()->create_course();

        // Create a teacher.
        $teacher = self::getDataGenerator()->create_user(['firstname' => 'searchforthis']);

        // Create a bunch of students.
        $student1 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis']);
        $student2 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis']);
        $student3 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis']);

        // Create a group.
        $group = self::getDataGenerator()->create_group(array('courseid' => $course->id));

        // Enrol the students.
        self::getDataGenerator()->enrol_user($student1->id, $course->id);
        self::getDataGenerator()->enrol_user($student2->id, $course->id);
        self::getDataGenerator()->enrol_user($student3->id, $course->id);

        // Enrol the teacher.
        $roleids = $DB->get_records_menu('role', null, '', 'shortname, id');
        self::getDataGenerator()->enrol_user($teacher->id, $course->id, $roleids['editingteacher']);

        // Add the teacher and two of the students to the group.
        groups_add_member($group->id, $teacher->id);
        groups_add_member($group->id, $student1->id);
        groups_add_member($group->id, $student2->id);

        // Set it so the teacher and two of the students have accessed the course within the last day, but only one of
        // the students is in the group.
        $accesssince = time() - DAYSECS;
        $lastaccess = new stdClass();
        $lastaccess->userid = $teacher->id;
        $lastaccess->courseid = $course->id;
        $lastaccess->timeaccess = time() - DAYSECS;
        $DB->insert_record('user_lastaccess', $lastaccess);

        $lastaccess->userid = $student1->id;
        $DB->insert_record('user_lastaccess', $lastaccess);

        $lastaccess->userid = $student3->id;
        $DB->insert_record('user_lastaccess', $lastaccess);

        // Now, when we perform the following search we should only return 1 user. A student who belongs to
        // the group and has the name 'searchforthis' and has also accessed the course in the last day.
        $userset = user_get_participants($course->id, $group->id, $accesssince + 1, $roleids['student'], 0, -1, 'searchforthis');

        $this->assertEquals($student1->id, $userset->current()->id);
        $this->assertEquals(1, iterator_count($userset));

        // Search for users without any group.
        $userset = user_get_participants($course->id, USERSWITHOUTGROUP, 0, $roleids['student'], 0, -1, '');

        $this->assertEquals($student3->id, $userset->current()->id);
        $this->assertEquals(1, iterator_count($userset));
    }

    /**
     * Test returning the participants on the front page.
     */
    public function test_user_get_participants_on_front_page() {
        $this->resetAfterTest();

        // Set it so that only 3 users have accessed the site within the last day.
        $accesssince = time() - DAYSECS;

        // Create a bunch of users.
        $user1 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis', 'lastaccess' => $accesssince]);
        $user2 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis', 'lastaccess' => $accesssince]);
        $user3 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis']);
        $user4 = self::getDataGenerator()->create_user(['firstname' => 'searchforthis', 'lastaccess' => $accesssince]);

        // Create a group.
        $group = self::getDataGenerator()->create_group(array('courseid' => SITEID));

        // Add 3 of the users to a group.
        groups_add_member($group->id, $user1->id);
        groups_add_member($group->id, $user2->id);
        groups_add_member($group->id, $user3->id);

        // Now, when we perform the following search we should only return 2 users. Users who belong to
        // the group and have the name 'searchforthis' and have also accessed the site in the last day.
        $userset = user_get_participants(SITEID, $group->id, $accesssince + 1, 0, 0, -1, 'searchforthis', '', array(),
            'ORDER BY id ASC');

        $this->assertEquals($user1->id, $userset->current()->id);
        $userset->next();
        $this->assertEquals($user2->id, $userset->current()->id);
    }
}